Flow of Energy in Ecosystems
Overview
Flow of Energy in Ecosystems
Life on Earth
Flow of Energy in Ecosystems
Energy Pyramid
- Energy is transferred from one trophic level to another.
- Energy can only flow through the ecosystem in one direction.
- At each trophic level organisms need sufficient energy to heat themselves and reproduce, therefore only ten percent of the energy in each level is transferred to the next higher level.
- Since only ten percent of the energy in a level is transferred to the next, most energy pyramids do not have more than 5 energy levels.
- Animals in higher trophic levels tend to be larger.
Study Tip
Think of climbing stairs, the higher you climb the less energy you have, so animals on the top of the pyramid only have a fraction of the energy that animals near the bottom of the pyramid do.
Complete the table with descriptions and examples
|
Trophic Levels
| Trophic Level | Individuals in the level | Examples (Insert an image for each) |
| 1 | Primary Producer | |
| 2 | Primary Consumer | |
| 3 | Secondary Consumer | |
| 4 | Tertiary Consumer |
Food Web and Food Chain
- A food chain is as system of organisms that transfer energy from one trophic level to anotherFood Web and Food Chain
- A food web shows the movement of energy through an entire ecosystem
| In a food web, organisms in a larger part of an ecosystem are interconnected with one another. The food web shown here covers both aquatic and land ecosystems | The food chain depicted here starts with plankton (producer), and ends with a hawk (secondary consumer). Food chains follow a specific path within the food web |
 |  |
Concept Check
What is the purpose of an energy pyramid?
What percent of the energy in a level is transferred to the next higher level?
- What does a food web show?
